This morning’s crash of an MV-22 Osprey off the coast of Australia marks the latest in a decades-long string of serious mishaps with the versatile aircraft. While originally intended to provide a unique mix of agility, speed, and range, the tilt-rotor aircraft has been persistently criticized as wildly expensive, ineffective, and unsafe.
The V-22, developed by Bell Helicopter and Boeing’s helicopter unit, is primarily designed to ferry ground troops into combat. Its distinctive tilting rotors let it take off vertically like a helicopter, then transition to a faster horizontal fixed-wing mode.
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But developing that concept to its fullest has proven extremely costly, and according to critics, the promise was never truly fulfilled. The project’s cost ballooned from a $68.7 million design contract in 1983 (the aircraft’s maiden flight took place in 1989) to $29.1 billion for research and procurement by 2009, when the estimated average cost per vehicle was $83.7 million. By 2012, some estimates put the total cost at $56 billion and the cost per unit at $100 million.
Variants of the venerable Black Hawk combat helicopter, by comparison, cost from $20 million to $40 million each.
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Despite its costs, the Osprey has earned a reputation for being dangerous and unreliable, in part thanks to the inherent challenges of its tilt-rotor design. In a testing period between 1991 and 2000, Ospreys crashed four times in non-combat operations, causing 30 fatalities. When it first went into service in 2007, Time magazine (which like Fortune is published by Time Inc.) famously branded it “a flying shame.” Since then, the Osprey has been involved in five more crashes, resulting in nine fatalities.
The V-22 made it through its troubled development and into service thanks to a complex welter of political agendas, largely driven by the Marine Corps. During the George H.W. Bush administration, for instance, Congress overruled attempts by then-Defense Secretary Dick Cheney to kill the program. And with time and money, many of the vehicle’s biggest problems have been solved or mitigated.
But even when it’s working as intended, the Osprey may not provide the mobility the military once hoped for. Jack McCain, Navy pilot and son of Sen. John McCain, in 2014 called the V-22 “awful” and a “piece of junk” fundamentally inferior to the older helicopter it was intended to replace, the Boeing CH-46. The younger McCain argued, among other points, that the craft is difficult to land under harsh conditions, undermining its reason for existing. The Osprey’s powerful downdraft also makes it less useful for raids and rescue operations, and difficult to land on aircraft carriers—the apparent circumstance of today’s crash.